The present invention relates to a chair which can be used in combination with a desk, and a seat body of the chair is configured to be swingable between a front end position and a rear end position. The front end position is a position in which the seat body is swung forward to a predetermined position. The rear end position is a position in which the seat body is swung rearward to a predetermined position.
Conventionally, in a place where desks and chairs are arranged in groups, such as a lecture room in a school, a chair is used which is configured such that, when seated, the chair is moved to the rear end position in which a seat body to be seated is swung rearward, and when not seated, the chair is moved to the front end position in which the seat body is swung forward and stored.
As such a chair, Unexamined Japanese Patent Publication No. 2002-028043 discloses an example of a chair in which a seat part and a base portion are connected by a front side leg portion and a rear side leg portion to form a four-link joint, thereby allowing the seat part to be swung in a front-and-rear direction. The seat part includes a backrest and a seat. The base portion is arranged on a floor surface. In the four-link joint of this chair, it is configured that a distance between a swing axis at an upper end part of the front side leg portion and a swing axis at an upper end part of the rear side leg portion, is longer than a distance between a swing axis at a lower end part of the front side leg portion and a swing axis at a lower end part of the rear side leg portion. When this chair is swung most forward at the front end position, the seat and the backrest are tilted forward.
In the chair constituted as above, the backrest is tilted forward at the front end position. Thus, when a person is passing behind the chair, even if a height of a waist area which is a relatively wider part of the person and a height of the upper end of the backrest of the seat part are approximately the same, the upper end of the backrest is not likely to be brought into contact with the waist area. Obstruction of a person's passage by the backrest could be inhibited.